Valve assembly including diameter reduction structure for trocar

ABSTRACT

A surgical seal assembly includes a sleeve housing adapted to be operatively connected to a surgical sleeve, a seal housing adapted for releasable mounting to the sleeve housing and having a seal member with inner portions adapted to permit passage of a surgical object in substantial sealed relation therewith, and a manual lock member associated with the sleeve housing. The manual lock member is adapted for movement relative to the seal housing between a first position corresponding to a release position of the seal housing to permit removal of the seal housing from mounting to the sleeve housing and a second position corresponding to a lock position of the seal housing to secure the seal housing to the sleeve housing. The manual lock member is preferably adapted for rotational movement relative to a longitudinal axis of the seal housing to move between the first and second positions thereof.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/380,942, which is a national phase application ofInternational Application No. PCT/US01131911, filed Oct. 12, 2001, whichclaims priority to U.S. Application Ser. No. 60/240,506, filed Oct. 13,2000, the entire contents of each application being hereby incorporatedby their entireties by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates to a mechanism for controlling theoperable inside diameter of a passageway through a valve assembly of atrocar housing. More particularly, the present disclosure relates to adiameter reduction structure that restricts the movement of smallsurgical instruments and. accommodates large diameter surgicalinstruments in the passageway of a trocar housing to facilitate themaintenance of a gas tight seal formed by the valve assembly.

2. Background of Related Art

Trocar valve assemblies preferably provide a fluid tight seal about asurgical instrument introduced through the trocar during a minimallyinvasive surgical procedure. A typical valve assembly includes an outerseal, which can be fixed or floating, in combination with additionalinner seals. Fixed outer seals are limited by their ability to sustain aseal when a smaller surgical instrument is moved off-axis relative to acentral axis of the trocar. Fixed seals are also limited by theirability to sustain their integrity when the surgical instrument isangulated. Such extreme ranges of motion of smaller diameter surgicalinstruments within the cannula can create a “cat eye” or crescent shapedgap in the fixed seal that can result in a loss of seal integrity.Additional problems include the flexibility of the seal in maintainingits integrity when both small diameter and large diameter surgicalinstruments are used.

Devices to restrict the diameter of a passageway in a trocar housinggenerally require an additional mechanism to be positioned on theproximal end of the trocar housing that restricts the range of motion ofsmall surgical instruments. These diameter reducing devices, however,typically employ additional seals and/or structures that requireadjustments by the user to accommodate different sized surgicalinstruments, thereby complicating the surgical process.

A continuing need exists for a diameter reducing structure that canlimit parallel off-axis as well as angular movements of small diametersurgical instruments and accommodate larger diameter surgicalinstruments without external adjustments.

SUMMARY

In accordance with a preferred embodiment, a surgical seal assemblyincludes a sleeve housing connected to a surgical sleeve, a seal housingincluding a seal member having inner portions adapted to permit passageof a surgical instrument in substantial sealed relation therewith, and amanual lock member movably mounted to the sleeve housing. The manuallock member is adapted for movement relative to the seal housing betweena first position corresponding to a release position of the seal housingto permit detachment of the seal housing from the sleeve housing and asecond position corresponding to a lock position of the seal housing tosecure the seal housing to the sleeve housing. The manual lock member ispreferably adapted for rotational movement relative to a longitudinalaxis of the seal housing to move between the first and second positionsthereof.

The manual lock member may include an annular member having at least onelocking surface adapted to engage at least one corresponding locking tabof the seal housing upon movement of the manual lock member to thesecond position. The annular member defines a central aperture forpermitting passage of the object. Preferably, the annular member definesa plurality of mounting recesses adjacent the central aperture and theseal housing has a plurality of locking tabs corresponding to themounting recesses. The mounting recesses are in general alignment withthe locking tabs of the seal housing when in the first position of themanual lock member to receive the locking tabs. The mounting recessesare thereafter displaced from the locking tabs upon movement of themanual lock member to the second position thereof. The manual lockmember may include a manual grip member depending radially outwardlyrelative to the longitudinal axis of the seal housing. The manual gripmember is dimensioned and configured for engagement by the surgeon.

The surgical seal assembly may include at least two stand-off elementsmounted within the seal housing distal of the seal member. The stand-offelements are adapted for pivotal movement between an initial positionand a pivoted position to permit passage of the surgical object. Thestand-off elements may be normally biased to the initial position torestrict off-axis movement of the surgical object with respect to alongitudinal axis of the seal housing. The at least two stand-offelements are preferably operatively coupled such that movement of atleast one of the stand-off elements between the initial and pivotedpositions causes corresponding movement of the other stand-off elements.

The sleeve housing may be adapted for connection to a cannula housing ofa cannula assembly.

In another preferred embodiment, a surgical system includes a cannulaassembly including a cannula housing and a cannula sleeve extending fromthe cannula housing. The cannula sleeve defines a longitudinal axis andhas a longitudinal passageway to permit passage of a surgicalinstrument. The surgical system further includes a surgical sealassembly incorporating first and second seal subassemblies. The firstseal subassembly includes a first housing having a seal member defininginner portions adapted to permit passage of a surgical object insubstantial sealed relation therewith. The second seal subassemblyincludes a second housing adapted for mounting to the cannula housing. Amanual lock member is adapted for movement between a first positioncorresponding to a release position of the first subassembly to permitremoval of the first subassembly from mounting to the secondsubassembly, and a second position corresponding to a lock position ofthe first subassembly to secure the first subassembly to the secondsubassembly. Preferably, the second subassembly includes the manual lockmember.

The manual lock member may be adapted for rotational movement relativeto the longitudinal axis to move between the first and second positionsthereof. One of the first and second seal assemblies includes a lockinglatch and the other of the first and second seal subassemblies includesa corresponding locking surfaces. The locking latch and the lockingsurface cooperate to secure the first seal subassembly to the secondseal subassembly upon movement of the manual lock member to the secondposition thereof. The other of the first and second seal subassembliesincludes a locking recess dimensioned for receiving the locking latchwhen the manual lock member is in the first position whereby uponrotation of the manual lock member to the second position the lockinglatch cooperatively engages the locking surface. Preferably, the firstseal subassembly includes the locking latch and the second sealsubassembly includes the locking recess and the locking surface. Thefirst seal subassembly preferably includes a plurality of lockinglatches and the second seal subassembly includes a pluralitycorresponding locking recesses for receiving the locking latches.

The second subassembly may include a zero closure valve adapted to opento permit passage of the surgical instrument and to substantially closein the absence of the surgical instrument.

A method for performing a surgical procedure is also disclosed. Themethod includes the steps of:

providing an access assembly including an access housing and an accesssleeve operatively connected to the access housing;

mounting a seal assembly to the access housing with the seal assemblyincluding a seal housing and a seal member mounted relative to the sealhousing, the seal member including inner portions adapted to form asubstantial seal about a surgical object introduced therethrough; and

securing the seal housing relative to the access housing by moving amanual lock member associated with the access housing to causecorresponding structure of the access housing and the seal housing tocooperatively engage in secured relation therewith.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the presently disclosed trocar diameterreduction structures for trocar are described herein with reference tothe drawings, wherein:

FIG. 1 is a perspective view of one preferred embodiment of a valveassembly and diameter reduction structure for trocars constructed inaccordance with the present disclosure;

FIG. 2 is an exploded perspective view of the valve assembly anddiameter reduction structure of FIG. 1;

FIG. 3 is a close-up perspective view of a proximal end portion of thevalve assembly and diameter reduction structure of FIG. 1;

FIG. 4 is a close-up perspective view of the valve assembly and diameterreduction structure of FIG. 3 partially disassembled showing a diameterreduction structure positioned in a diameter reduction structurefoundation element;

FIG. 5 is a close-up perspective view of the valve assembly and diameterreduction structure of FIG. 1 partially disassembled showing, a secondseal;

FIG. 6 is a close-up perspective view of a linking member in accordancewith the disclosure of FIG. 1;

FIG. 7 is a close-up perspective view of a distal end portion of thediameter reduction structure foundation element in accordance with thedisclosure of FIG. 1;

FIG. 8 is a close-up perspective view of a stand off in accordance withthe disclosure of FIG. 1;

FIG. 9 is a cross-sectional view of the valve assembly and diameterreduction structure of FIG. 1 along lines 9-9;

FIG. 10 is a close-up of the cross-sectional view of the valve assemblyand diameter reduction structure of FIG. 9;

FIG. 11 is an exploded view of the diameter reduction structure and thediameter reduction structure foundation element of FIG. 4;

FIG. 12 is a perspective view of the valve assembly and diameterreduction structure of FIG. 1 being operationally employed with a largediameter surgical instrument passing through the valve assembly anddiameter reduction structure and into a tissue portion of a patient;

FIG. 13 is a close-up of the cross-sectional view of FIG. 12 along lines13-13 showing the repositioning of the diameter reduction structure forthe large diameter surgical instrument;

FIG. 14 is a close-up cross sectional view of the valve assembly anddiameter reduction structure of FIG. 10 showing a small diametersurgical instrument being positioned at least partially therein;

FIG. 15 is the cross-sectional view of FIG. 14 showing the diameterreduction structure controlling the angular movement of a small diametersurgical instrument positioned therein;

FIG. 16A is a top view of a second embodiment of a valve and diameterreduction structure constructed in accordance with the presentdisclosure;

FIG. 16B is a cross-sectional view of FIG. 16A along lines 16B-16Bshowing a representative movement of one stand off member of thediameter reduction structure;

FIG. 16C is. a cross-sectional view of FIG. 16A along lines 16C-16Cshowing the diameter reduction structure in a first position;

FIG. 17 is a perspective view of a proximal end of a third embodiment ofa diameter reduction structure for trocar constructed in accordance withthe present disclosure;

FIG. 18A is across-sectional view of the trocar illustrating thediameter reduction structure of FIG. 17 along line 18A-18A;

FIG. 18B is a cross-sectional view of the valve assembly and diameterreduction structure of FIG. 18A along line 18B-18B;

FIG. 18C is a cross-sectional view of the valve assembly and diameterreduction structure of FIG. 18A along line 18C-18C;

FIG. 19 is a cross-sectional side view of a fourth embodiment of thevalve assembly and diameter reduction structure constructed inaccordance with the present disclosure;

FIG. 20A is an enlarged cross-sectional view of the second embodiment ofthe stand off configuration of the diameter reduction structure fortrocar of FIGS. 18A, 18B, and 18C;

FIG. 20B is an enlarged cross-sectional view of the stand offconfiguration of the diameter reduction structure for trocar of FIG. 19;

FIG. 20C is partial cross-sectional perspective view of a fifthembodiment of a diameter reduction structure constructed in accordancewith the present disclosure;

FIG. 21 is a top view of a sixth embodiment of a valve assembly anddiameter reduction structure for trocar having a movable diameterreduction. assembly constructed in accordance with the presentdisclosure;

FIG. 22A is a cross-sectional view of the valve assembly and diameterreduction structure for trocar stand for trocar of FIG. 21 along line21A-21A;

FIG. 22B is the cross-sectional view of the valve assembly and diameterreduction structure for trocar of FIG. 22A with the stand off assemblyin the second position;

FIG. 22C is the cross-sectional view of the stand off configuration ofFIG. 22A with the stand off assembly in a third position; and

FIG. 23 is a cross-sectional view of an alternate embodiment of thevalve assembly and diameter reduction structure of FIG. 22A;

FIG. 24 is a perspective view of another alternate embodiment of theseal assembly shown mounted to a cannula assembly in accordance with theprinciples of the present disclosure;

FIG. 25 is a perspective view with parts separated of the seal assemblyand cannula assembly in accordance with the embodiment of FIG. 24illustrating the components of the first and second seal subassemblies;

FIG. 26 is a side cross-sectional view taken along the lines 26-26 ofFIG. 24 illustrating the seal assembly mounted to the cannula housing ofthe cannula assembly in accordance with the embodiment of FIGS. 24-25;

FIG. 27 is a perspective view illustrating mounting of the first sealsubassembly to the second seal subassembly in accordance with theembodiment of FIGS. 24-26;

FIG. 28 is a view illustrating the mounting tabs of the first sealsubassembly in accordance with the embodiment of FIGS. 24-27;

FIG. 29 is a view illustrating the mounting recesses of the second sealsubassembly for receiving the mounting tabs of the first sealsubassembly in accordance with the embodiment of FIGS. 24-28;

FIG. 30 is a view of the seal assembly illustrating the manual lockmember in a first position corresponding to a release position inaccordance with the embodiment of FIGS. 24-29; and

FIG. 31 is a view of the seal assembly illustrating the manual lockmember in a second position corresponding to a locked position inaccordance with the embodiment of FIGS. 24-30.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present disclosure contemplates the introduction into a body of apatient a trocar adapted for receiving all types of surgical instrumentsincluding clip appliers, graspers, dissectors, retractors, staplers,laser fibers, endoscopes, as well as electrosurgical cutting,coagulating, and ablation devices, and the like. All such objects arereferred to herein as “instruments”.

Referring now in specific detail to the drawings in which likereferenced numerals identify similar or identical elements throughoutthe several views, and initially to FIG. 1, a novel valve assembly anddiameter reduction structure for trocar 100 is shown constructed inaccordance with a preferred embodiment of the present disclosure andintended to be used in combination with a conventional trocar assemblyand cannula 50 defining a passageway 25 aligned with a centrallongitudinal axis-X. Passageway 25 defines a first operational area.

Valve assembly and diameter reduction structure 100 includes diameterreduction assembly 200 located adjacent a proximal end portion and valveassembly 300 located adjacent a distal end portion. The diameterreduction assembly 200 of the present disclosure, either alone or incombination with valve assembly 300 provides a seal between a cavityformed in the patient and the outside atmosphere during and subsequentto insertion of an instrument through cannula 50. Moreover, valveassembly and diameter reduction structure 100 is capable ofaccommodating instruments of varying diameter, e.g. from ranges such as5 mm to 12 mm, by providing a gas tight seal with each instrument duringsurgical procedures. The flexibility of the present valve assembly anddiameter reduction structure 100 to retain a fluid tight seal greatlyfacilitates endoscopic surgery where a variety of instruments havingdiffering diameters are often needed during a single surgical procedureand off axis movements as well as small tool surgical angulation isemployed.

Valve assembly and diameter reduction structure 100 is preferablydetachably mountable to a proximal end 54 of cannula 50. During surgery,the surgeon can remove the diameter reduction assembly 200 from valveassembly 300 at any time during the surgical procedure and, similarly,mount diameter reduction assembly 200 to valve assembly 300 toreconfigure diameter reduction structure and valve assembly 100. Inaddition, diameter and valve assembly 100 may be readily adapted to bemounted to conventional cannulas of differing structures, material, andlengths. The ability of diameter reduction assembly 200 to detach fromvalve assembly 300 facilitates specimen removal through cannula 50 andreduces the profile of cannula 50 when diameter reduction assembly 200is not needed at a particular point of the surgical procedure. It isenvisioned that assembly 200 can also be configured to adapt to avariety of valve assemblies.

Referring now to FIGS. 2-3, one preferred embodiment of the novel valveassembly and diameter reduction structure 100 of the present disclosurewill be discussed in detail. Diameter reduction assembly 200 includes anend cap 110, a first seal 125, diameter reduction structure housing orfirst housing 210, a first O-ring 225, a diameter reduction structure240, and a diameter reduction structure foundation element 280. Diameterreduction structure foundation 280 is connected with valve assembly 300.Seal housing 30 is configured to be removably connected to cannula 50.

End cap 110 is generally tubular in shape and includes a distal endportion 112 and a proximal end portion 114. An annular shaped disc 116defines a hole 115 aligned with the central longitudinal axis. End cap110 is removably connected with diameter reduction structure housing210.

First seal 125 is sealingly positioned between a distal side of theannular shaped disc 116 of end cap 110 and a proximal end portion ofdiameter reduction structure housing 210. First seal 125 forms a firstexterior seal of assembly 100 and may be any conventional type of sealsuch as, but not limited to, a fixed or floating seal.

Diameter reduction structure housing 210 has a generally hemisphericalshell shape decreasing in circumference from a distal end portion 212 toa proximal end portion 214. Correspondingly, distal end portion 212defines a hole 215 having a diameter larger than the diameter defined byannular portion 213 of proximal end portion 214. Hole 215 isconcentrically aligned with the central longitudinal axis-X. Proximalend portion 214 is configured to be connectively received by distal endportion 112. Distal end 212 includes an outside cylindrical portion 216having a scalloped surface to facilitate handling thereof. A firstO-ring 225 is seated on the inside surface of diameter reductionstructure housing 210 in the vicinity of annular portion 213.

Referring now to FIGS. 2 and 4, diameter reduction structure foundationelement 280 is configured to seat diameter reduction structure 240 onits proximal end portion 284 and support the movement of the diameterreduction structure 240 through a predefined range of motion and, incooperation with housing 210, provides a suitable support structure forstand offs 250 when limiting the operational diameter of the passageway25 through valve assembly and diameter reduction structure 100.Foundation element 280 has an outside cylindrical surface 286 andfurther defines a distally positioned generally tubular shaped portion285 centered on the longitudinal axis.

Diameter reduction structure 240 includes a stand off assembly 245having three stand off members 250 interconnected by a linking mechanism270 having three linking members 271 in this one preferred embodiment.Stand offs 250 provide a predetermined degree of control over themovements of an instrument positioned within assembly 100. Linkingmechanism 270 integrates and synchronizes the movement of stand offs250.

Each linking member 271 is connected with and positioned between twoadjoining stand offs 250 such that diameter reduction structure 240forms an approximately hexagonal configuration of alternating stand offs250 and linking members 271 centered around longitudinal axis X.

Each stand off member 250 includes a cylindrical cogwheel portion 252defining a longitudinal axis-Y (see FIG. 8) and having opposingcylindrical end portions 254 with gears having cogs or teeth 255extending parallel to longitudinal axis-Y. Linking members 271 also havea cylindrical shape defining a longitudinal axis-Z (see FIG. 6) andopposing ends 274 with gears having cogs or teeth 275. Teeth 275 extendparallel with the longitudinal axis-Z. Linking members 271 and stand offmembers 250 are positioned in diameter reduction structure foundationelement 280 such that each respective cog 275 or 255 is configured,dimensioned, and positioned with suitable angular orientation to fitinto a corresponding beveled slot 257 or 277, respectively, of theadjoining interrelated portion of diameter reduction structure 240 tointegrate and coordinate the simultaneous movement of each stand off250.

Linking members 271 provide a synchronizing function for the pivotalmovement of stand offs 250 throughout their range of movement, whereinthe diameter reduction structure 240 is at least partially repositionedto accommodate a larger diameter surgical instrument. The limitations ofmovement of the diameter reduction structure 240 in the second positioninclude factors such as the diameter of the cannula, shape of the standoff, and internal portions of the trocar that limit the pivotal orrotational type travel of stand offs 250 away from the longitudinalaxis. The second position is defined as when stand offs 250 are pivoted,flexed, or rotated in their seated position in diameter reductionstructure 280 in a generally arcuate path distally and away from thelongitudinal axis to increase the passageway 25 diameter defined by theinterrupted annular barrier of diameter reduction structure 240.

Diameter reduction structure housing 210 and diameter reductionstructure foundation element 280 are configured to support thepositioning, diameter control function, and movement of diameterreduction structure 240. Housing 210 and foundation element 280 may beadapted to interface with a variety of different end caps, first seals,and seal housings, for example, as well as varying cannula sizes.

Referring now to FIGS. 2 and 5, valve assembly 300 includes a secondO-ring 335, a first seal support member 350, a second seal 365, a secondseal support member 380, a third O-ring 395, and a seal housing orsecond housing 310 configured for connecting to cannula 50. Diameterreduction structure foundation 280 provides seating for second O-ring335 providing a seal between distal end 282 and a proximal end portion354 of first seal support element 350.

A second seal 365 includes a flange 367 for being sealingly positionedbetween a distal end portion 352 of first seal support element 350 and aproximal end portion 384 of second seal support element 380. First sealsupport element 350 is generally annular in shape with an outsidecylindrical surface 356 and has three distally extending tabs 358. Asecond seal support element 380 also has a generally annular shape withan outside cylindrical surface 386 and is configured with radiallyextending tabs 388. A third O-ring 395 provides a seal between secondseal support element 380 and seal housing 310.

Seal housing 310 has a proximal end portion 314 including radiallyaligned slots 318 configured to correspondingly mate with tabs 388 and adistal end portion 312 configured to mate with cannula 50 utilizing asuitable attachment mechanism such as a bayonet or threaded connection.

Seal housing 310 further includes two diametrically opposed cantileveredportions 325. Each cantilevered portion includes two opposed notches 326having suture attachment fixtures 327 generally perpendicular toportions 325. Attachment fixtures 327 include a cylindrical portion 328and a hemispherical portion 329 configured for an easy tie off ofsutures for the positive retention of the trocar assembly in positionwithin the patient against the sufflation pressure typically employed inminimally invasive surgery.

Second seal 365 is shown as a duck bill type seal, but it may be anyseal system such as a frusto-conical seal, for example, that may beadapted to perform the function of a second seal. Second seal supportelement 380 is positioned in seal housing 310.

End cap 110, diameter reduction structure housing 210, diameterreduction structure foundation element 280, first seal support element350, second seal support element 380, and seal housing 310 arepreferably made of a medical grade plastic, metal, or compositematerials having suitable strength and resilience for its application.In one preferred embodiment, the above assemblies are injection moldedusing a medical grade plastic. The O-rings are made of a medical gradeplastic or rubber suitable for providing a fluid tight seal betweengenerally rigid structural members.

Referring now to FIGS. 6-8, in one preferred embodiment, linking member271 is shown aligned with longitudinal axis-Z. A band 272 having anincreased circumference and predetermined width is positioned on thecylindrical surface 274 of each linking mechanism 270. Cogs 275 have afirst arcuate width congruent at the outside surface of cylindricalportion 274 that tapers or bevels to a narrower second arcuate width atthe opposing side of each cog 275. Thus, cogs 275 extend inwardly fromsurface 274 to a predetermined point between surface 274 andlongitudinal axis-Z. Cogs 275 extend beyond and at least partiallysurround a recessed flat portion 278 that may include at least one pin279. Pin 279 is concentric with longitudinal axis-Z and extends axially.Slots 277 are defined by cogs or teeth 275 and beveled portions ofcylindrical portion 274.

Diameter reduction structure foundation element 280 is shown with distalend portion 282 connecting with tubular shaped portion 285 and proximalend 284. Tubular shaped portion 285 is positioned to guide instrumentsbeing inserted into the second seal and has an inside diameter at leastapproximately equal to the diameter of passageway 25. Radially extendingtabs 287 and 289 positioned on tubular shaped portion 285 andcylindrical portion 286, respectively, are configured and dimensioned tosealingly engage first seal support element 350 with foundation element280 in combination with O-ring 335. Cylindrical portion 286 has anannular shape including a radially extending lip 281. Proximallyextending tabs 288 and at least partially concave cavities 290 areconfigured to support the rotation or flexing of diameter reductionstructure 240 within proximal end portion 284.

Stand off members 250 have a head 260 connected by an arm 256 to a baseportion 251 with opposing cylindrical end portions 254 aligned with alongitudinal axis-Y. A tubular band 252 has a circumference greater thanthe circumference of end portion 254. A longitudinally aligned notch 252a is formed in band 252 near the base of arm 256. Cogs 255 have a firstarcuate width congruent with the surface of cylindrical portion 254 thattapers to a narrower second arcuate width at the opposing side of eachcog 255. Thus, cogs 255 extend inwardly from surface 254 to apredetermined point between surface 254 and longitudinal axis-Y. Slots257 are defined by cogs or teeth 255 and beveled portion of cylindricalend portion 254. Cogs 255 extend along axis-Y beyond and at leastpartially surround a recessed flat portion 258 that may include a pin259. Pin 259 is concentric with longitudinal axis-Y and extends axiallyfrom portion 258. Head 260 has a generally hemispherical or bulbousshape having an exterior surface and a concave interior surface 266.

Head 260 includes a first side 262 having a generally planar face and anopposing tapered second side 268. First side 262 includes a cantileveredextension 261. A third side 264 includes a generally convex portion andbeveled side portions 265. A fourth side 266, opposing, the third side264, has a generally planar face that is connected with arm 256. Head260 also includes a centrally positioned segmented concave notch 263approximately perpendicular to longitudinal axis-Y. The generallyconcave shape of notch 263 is configured and dimensioned to accommodatea limited degree off axis movement by small surgical tools when diameterreduction structure 240 is in a first or initial position. Arm 256connects head 260 with base portion 251.

Diameter reduction structure 240 components, including stand offassembly 245 and linking mechanism 270, are preferably fabricated fromat. least one medical grade plastic, laminates of medical gradeplastics, or composite materials of suitable flexibility, bias,rigidity, and compressive strength for application as diameter reductionstructure. Different materials may also be bonded together in thisstructure depending on the application, for example, head 260 may befabricated from one medical grade plastic that is of greater resiliencythan a second medical grade plastic that forms arms 256. Similarly,linking members 271 may be formed of similarly suitable one or moremedical grade plastic or composite materials.

Further, the system of cogs synchronizing the movement of stand offs 250and linking members 271 are but one type of linking mechanism 270 knownby those skilled in the art suitable for synchronizing the movements ofstand offs 250 and other suitable alternative mechanisms such as, butnot limited to a pulley system, a flexible synchronizing shaft, or anarticulated joint performing the same function are envisioned.

Referring now to FIGS. 9, and 10, valve assembly and diameter reductionstructure 100 and cannula 50 are shown in cross-section. First seal 125includes concave or arcuate membrane portion 127 that extends radiallyinwardly and distally forming a distal end portion 128 defining a hole129. Portions 127 are in close proximity to or abut stand off members250. Stand off members 250 are shown in a first position having anorientation generally perpendicular to central longitudinal axis-X. Thedepth and width of segmented notches 263 are shown relative to hole 129and second side 264 and provide a limited and increased degree of offaxis movement or angular movement of small surgical instruments.

Stand offs 250 include a base portion 251 positioned in proximity to orabutting cantilevered portion 218. Cantilevered portion 220 includeswall 222 configured to act as a stop to limit the radially outwardmovement of heads 260 of stand off members 250. The material ofconstruction of stand off members, and especially head 260, may beselectively controlled to provide a range of flexibly compressive biasagainst parallel off axis and angular movements or surgical instruments.

Diameter reduction structure housing 210 at least partially enclosesdiameter reduction structure foundation element 280 and first sealsupport element 350. Flange 367 of second seal 365 is secured betweenfirst seal support element 350 and second seal support element 380. Sealhousing 310 at least partially encloses second seal support element 380.Cannula 50 connects with distal end portion 312 of seal housing 310.

In FIG. 11, diameter reduction structure 240, shown as an integratedassembly in the first position, for placement within diameter reductionstructure foundation element 280. Foundation element 280 is configuredto provide suitable positioning for diameter reduction structure 240 tocontrol the operable diameter and thus improving the ability of thesealing system of assembly 100 to retain its integrity during proceduresutilizing small instruments. This includes a suitable supportingstructure for stand offs 250 to act as a barrier providing a controlledlimitation to the movement of surgical instruments and supporting themovement of diameter reduction structure 240 between the first andsecond positions.

The first position of structure 240 being defined by. heads 260 formingan interrupted annular barrier structure suitable for controlling forcesin a plane generally orthogonal to the longitudinal axis-X resultingfrom parallel off axis and angular movements or movements generallyorthogonal to the longitudinal axis of small surgical instrumentspositioned in passageway 25. The third sides 264 of heads 260 definingthe second operable area in the first position.

In the first position, beveled portions 265 of heads 260 define gaps orinterruptions in the annular barrier structure formed by diameterreduction structure 240. The size of the gap is controlled by the shapeand position of heads 260 and is configured to ensure smaller diametersurgical instruments are precluded from passing between heads 260.Diameter reduction structure 240 further includes a controlled biasconfigured to resist the movement of reduction structure 240 radially inan outward direction as well as from the first position to the secondposition. The bias in structure 240 also serves to return structure 240to the first position after the removal of the larger diameter surgicalinstrument.

The second position being defined by diameter reduction structure 240moving at least partially distally to accommodate the unrestrictedpassage or of individual larger sized diameter surgical instrumentsthrough diameter reduction structure 240 and cannula 50.

Foundation element 280 includes at least partially concave seatingpositions 296 for linking members 271 and 290 for stand off members 250.Seating positions 290 define an interrupted channel having two distinctseats or supports 292 configured and dimensioned to receive cylindricalend portions 254. Band 252 is positioned between supports 292. Seatingpositions 290 further include an arcuate support member 294 with aproximally extending straight portion 299.

Seating positions 296 define an at least partially concave channelportions 298 separated by a slot or recess 297 configured anddimensioned to receive surface 274 and band 272 of linking member 271.Seating positions 296 include a proximally extending straight portion299.

Seating positions 290 and 296 are structurally supported by a proximallyextending member 295. Member 295 is connected by arms to portions 292and 298 and is configured to structurally support portions 292 and 298from excessive deflection or movement.

Seating positions 290 and 296 provide the alignment; spacing, andangular orientation critical for the interrelation of cogs 255 and 275with their respective slots 277 and 257 for the synchronizing of themovements of stand offs 250 and linking members 271. In addition,diameter reduction structure 240 includes a bias to the first positionas individual components or as an assembly either as a result of itspositioning within diameter reduction structure foundation element 280,a separate bias member such as an elastic band, or by combinationsthereof. When fully assembled with diameter reduction structure housing210 (see FIG. 2) and diameter reduction structure foundation 280,diameter reduction structure 240 is capable of performing its functionsat any angle or in any direction of use without any operator action.

Referring now to FIGS. 12 and 13, diameter reduction structure 100 isshown in an operational position. A large diameter medical instrument 80defining a second longitudinal axis is positioned through valve assemblyand diameter reduction structure 100 and cannula 50. A large diametersurgical instrument is an instrument having a diameter or ancross-sectional area orthogonal to the second longitudinal axis lessthan a first diameter or first operable area of passageway 25, butgreater than the second diameter or second operable orthogonal to thecentral longitudinal axis defined by the stand off assembly in the firstposition. Similarly, a small diameter surgical instrument 60 defining afirst longitudinal axis has a diameter or cross-sectional areaorthogonal to the first longitudinal axis less than the second diameteror second operable defined by the stand off assembly in the firstposition. Thus, the large instruments by definition being larger thanthe second operable area must at least partially deflect stand offassembly 240 distally in order to enter the passageway. In contrast, thesmall instruments can be positioned axially within the second operablearea without deflecting stand off assembly 240. In this one preferredembodiment, large instruments are those defined as having diametersgreater than 5.5 mm and small instruments those defining diameters equalto or less than 5.5 mm. The 5.5 mm distinction between large and smallinstruments is relative to the diameter of the passageway defined in thetrocar and can vary depending upon the diameter of the trocar apparatusthe valve assembly and diameter reduction structure 100. When largediameter instrument 80 is moved distally along central longitudinalaxis-X through first seal 125 and into contact with diameter reductionstructure 240, the axially aligned force component moving large diameterinstrument 80 has to overcome the bias configured to retain diameterreduction structure 240 in the first position, as shown in FIG. 10.

As the force behind instrument 80 exceeds the bias configured tomaintain diameter reduction structure 240 in the first position,diameter reduction structure 240, pivots or rotates in a generallyarcuate movement in a generally distal direction initially and thencontinues its pivotal or rotational arcuate movement, as shown by arrows“A” and “B”, away from the central longitudinal. axis to define thethird operable area and accommodate the passage of large diameterinstrument 80. The amount of bias employed to retain diameter reductionstructure 240 in the first position is controlled by factors such as thematerials of construction of diameter reduction structure. 240 as wellas the methods employed of securing diameter reduction structure 240 inposition in diameter reduction structure foundation element 280.

When forced towards. the inside diameter of wall 356 by the shaft oflarge diameter of instrument 80, stand offs 250 move to a secondposition wherein face 262 of head 260 is placed approximately parallelwith and in apposition to wall 356. The spatial relationship betweenwall 356 and diameter reduction structure 240 in the second position isa function of individual trocar interior configurations, the insidecircumference of passageway 25, and the intended application of thevalve assembly and diameter reduction structure 100. Valve assembly anddiameter reduction structure 100 is configured to provide suitable spacefor the pivoting or flexing of diameter reduction structure 240 andstill accommodate larger diameter instruments 80 that conform with themaximum inside diameter for a given. cannula 50. Upon withdrawal oflarger diameter instrument 80, diameter reduction structure 240 isbiased to reposition to a first position wherein a portion of each standoff 250 is adjacent wall 220.

Referring now to FIGS. 14 and 15, stand off members 250 are shown in afirst or diameter reduction position, wherein head 260 extends in agenerally radial direction relative to longitudinal axis-X. Cantileveredportion 222 provides a generally rigid barrier configured tostructurally support and limit the radial displacement of head 260.Diameter reduction structure 240 in the first position is configured toaccommodate the penetration of smaller diameter instruments 60 throughvalve assembly and diameter reduction structure 100 and into cannula 50without any movement.

When in this first position, stand off member 250 is placed at leastpartially in axial compression by a force with a component perpendicularto central longitudinal axis-X as a result of the orthogonal or angularmovements of a small diameter surgical instrument 60. Each stand offmember 250 is mounted in diameter reduction assembly 200 to provide alimit to excessive parallel off axis and angular movements of smalldiameter surgical instruments 60.

A small diameter surgical instrument 60 is positioned through seal 125and into cannula 50 typically with little or no substantial contact withdiameter reduction structure 240. When small diameter surgicalinstruments 60 are manipulated to make off axis or angular movements,however, small diameter surgical instruments 60 come in contact with atleast one head portion 260 and the inside circumference of cannula 50which act in combination as two separate and approximately parallelstructural barriers to control outwardly directed off axis and angularmovements away from central longitudinal axis-X. The combination of head260 and cantilevered portion 222 may be configured as a rigid orflexible biased structure. This controlling mechanism functions to boundthe operational movements by small diameter surgical instruments 60,sufficiently to retain the integrity of the sealing system.

Referring now to FIGS. 16A, 16B, and 16C, in another preferredembodiment, valve assembly and diameter reduction structure 500 includesa proximal end portion or diameter reduction assembly 600 and a valveassembly 700 similar to the previous embodiment, however, diameterreduction structure 640 is positioned proximal to a first seal 525.

Diameter reduction structure 500 includes an end cap 510, a diameterreduction structure housing 610, a diameter reduction structure 640, adiameter reduction structure foundation element 680, and as required afirst O-ring.

End cap 510 has a generally cylindrical shape including a distal endportion 512 and a proximal end portion 514. Proximal end portion 514includes an annular shaped disc or portion 516 defining a hole 515aligned with the central longitudinal axis-X. In this configuration,annular portion 516 may be a rigid plastic or a flexible membrane notconfigured to be a seal. Thus, hole 515 could be configured as a rigidor flexible barrier and having a diameter at least equal to the. insidediameter of a cannula 50 in a rigid configuration.

Diameter reduction structure housing 610 has a generally hemisphericalshell shape decreasing in circumference from a distal end portion 612 toa proximal end portion 614. Proximal end portion 614 includes an annularportion 613 defining hole 615. Hole 615 preferably has a larger diameterthan hole 515. Proximal end portion 614 is configured to be connectivelyreceived by distal end portion 512. Distal end portion 612 includes anoutside cylindrical portion 616 having a scalloped surface to facilitatehandling thereof.

Diameter reduction structure 640 includes a stand off assembly havingthree stand off members 650 and a linking mechanism 670 is positionedproximal to a first seal 525. Stand offs 650 provide a predetermineddegree of control over and limitation to the movements of instrumentspositioned within assembly 600. Linking mechanism 670, in the form ofthree linking members 671, integrate and synchronize the movement ofstand offs 650. While the specific configuration of stand off members650 or linking mechanism 670 may vary, stand off assembly 645 isemployed operationally as described in all of the embodiments herein tolimit the off-axis and angular movements of small surgical instruments.

Diameter reduction structure foundation element 680 is configured toseat diameter reduction structure 640 on. its proximal end portion 682and includes at least partially cantilevered seating positions 690configured to support and control the movement of reduction structure640 throughout a predefined range of motion as at least partiallyrepresented by arrow “A”. A distally extending tubular portion 685 isconfigured for the positioning of first seal 525. First seal 525 ispositioned approximately orthogonal to longitudinal axis-X and may be afixed or—a floating type seal.

A first seal support element 750 has a generally tubular shape with adistal end portion 754 abutting a proximal side of cantilevered seatingportion 690 and a distal end 752. First support element 750 has aninside wall 756 that may be configured to limit the distal range ofmotion of stand offs 650. A cantilevered portion 753 of first sealelement 750 is positioned to secure and seal a flange 767 of a secondseal 765 in positioned between a proximal portion of second seal supportelement 780.

A distal end 752 of first support element 750 at least partiallyencloses and sealingly positions a flange 767 of second seal 765 incooperation with a distal end portion 782 of a second seal supportelement 780. Second seal 765 may be any type of seal, but is preferablya duck bill type seal commonly configured for use with a fixed orfloating first seal. In the preferred embodiment, second seal 765 is aduck bill type seal extending distally into a seal housing 710.

Seal housing 710 includes a proximal portion 714 configured to secureand at least partially enclose second seal 765 and at least a portion ofsecond seal support element 780 and first seal support element 750.Second seal support element 780 also has a generally annular shape andis configured to lock with and engage first seal support element 750.Seal housing 710 has a distal end portion 712 configured to mate with acannula.

Valve assembly and diameter reduction structure 500 is configured as anassembly for controlling the off axis and angular movements of smallsurgical instruments externally or proximally to the sealing system.This configuration reduces the strain placed on the first seal byfurther limiting the range of angular motion to which the first seal issubjected to by small surgical instrument manipulation and therebyimproving the integrity of the trocar sealing system. In addition, whilevalve assembly and diameter reduction structure 500 may be removablyconnected to a correspondingly dimensioned cannula 50, it is alsoenvisioned that end cap 510, housing 610, diameter reduction structure640, and foundation element 680 may be readily adapted as an integratedassembly, for example, with or without an integrated first seal 525, foruse with a wide range of trocar assemblies having fixed or floatingseals to advantageously control off-axis and angular movements of smallsurgical instruments without interrupting the integrity of the sealedportions of the trocar.

Referring now to FIGS. 17 and 18A-18C, one of the preferred embodimentsof a valve assembly and diameter reduction structure 800 includes aproximal end portion or diameter reduction assembly 900 and a distal endportion or valve assembly 1000. Diameter reduction structure 940 ispositioned distal to a first seal 825 and within a diameter reductionstructure housing 910.

Diameter reduction structure 940 is illustrated with a stand offassembly. 945 having three stand offs 950 and three linking members 971positioned in a diameter reduction structure foundation 980.—While thegeneral configuration of diameter reduction structure foundation 980 andlinking members 971 are structurally and operationally similar toearlier embodiments, stand offs 950 have a different configuration headportion 960, similar to that depicted in FIG. 16A, with side portion 965having a generally planar shape and a width approximately equivalent toarm 956.

Head portion 960 may also include an attachment mechanism 963 and acantilevered extension or flange 967. Flange 967 extends radially fromhead 960 toward base 961 in the first position. In the second positionof stand off 950, flange 967 can be configured with a suitable length toat least partially limit the range of movement of stand off 950 bycontacting an inside wall of diameter reduction structure housing 910.Attachment mechanism 963 is configured to receive and retain anannularly shaped bias member 969 on stand off 950 throughout its rangeof motion. Annularly shaped biased member 969 is configured to biasstand offs 950 to the first position, provide an additional bias whenoff axis or angular movements act to compress a stand off 950 in aradially outward direction against the. diameter reduction structurefoundation 980 or housing 910, and act as an uninterrupted barrier topreclude smaller diameter surgical instruments from intruding betweenstandoffs 950.

The combined effect of attachment mechanism 963, flange portion 967, andbias member 969 is the control by stand off assembly 940 of the movementof smaller diameter surgical instruments when forces having a generallyorthogonal orientation to the longitudinal axis are employed as well asthe ability of stand off assembly 940 to automatically accommodatelarger diameter instruments.

In FIG. 19, an additional preferred embodiment of valve assembly anddiameter reduction structure 1200 is configured with a diameterreduction structure 1340 including a stand off assembly 1345 having fourdiametrically opposed stand offs 1350 independently positioned within adiameter reduction structure foundation. 1380. Each stand off 1350independently pivots, without a linking mechanism, to limit off-axis andangular movements of small instruments.

Stand off members 1350 include ahead 1360, an arm 1356, and a baseelement 1351 configured for mounting with foundation 1380. Stand off1350 can be fixedly mounted to foundation 1380 or example, or in thealternative base element 1351 may be pivotally positioned on foundation1380 and retained in place using a positioning element (not shown). Abias is employed to position stand off 1380 to a first position adjacenthousing 1310. As a further alternative embodiment, a linking mechanismmay be positioned to be operative with heads 1360 to perform, forexample, one or both functions of the linking mechanism shownpreviously. Alternative head 1360 configurations include havingtelescoping, tongue and grooved, or beveled gear mechanisms thatinterrelate stand offs 1380 into an approximately contiguous annularstructure throughout their range of motion.

A bias inherent in stand off 1350 or in combination with its positioningelement to the diameter reduction structure foundation 1380 maintainsstand offs 1350 in the first position unless deflected by a largediameter surgical instrument. As shown in other embodiments, diameterreduction structure 1350 may be employed proximal to or distal to afirst seal. Stand offs 1350, in this configuration, also include abulbous shaped head 1360, similar to that of head 260 for controllingthe movements of smaller diameter surgical instruments.

In FIGS. 20A and 20B, two embodiments of stand off members 950 and 1350are shown corresponding to FIGS. 18A-18C and 19, respectively. These twomajor configurations of stand offs, however, are only to be consideredto be representative of all the stand off configurations describedherein. Stand off members 950 and 1350 include base portions 951 and1351 forming—an axis “y” at angle alpha (α) with an axis “Y”. Axis “Y”is perpendicular to central longitudinal axis “X”. Heads 960 and 1360define an axis “x” at an angle theta “θ” with the “X”. Depending uponthe configuration of the trocar housing and application, angles “α” or“θ” may be coincident with their respective “Y” and “X” axes or extendto the opposing side of their respective axes in alternative embodimentsof stand offs 950 and 1350. Axis “X” is parallel to central longitudinalaxis “X”.

All the stand offs described herein provide a generally compressionresistant biased structure against forces acting in a plane having agenerally orthogonal orientation to the “X” or central longitudinalaxis. It is envisioned that stand offs 950 and 1350, as well as all theother stand off variations herein are configured and positioned relativeto structures such as the diameter reduction housings to at leastprovide a generally compression resistant biased structure againstforces in planes at angles ranging from plus or minus approximately 15degrees from an angle orthogonal to the central longitudinal axis.

Individual stand off members 950 and 1350 can include varying headportion 960 and 1360 configurations such as wing extensions or flangesthat overlap, interrelate, or interleave between adjacent stand offs 950and 1350. A retention mechanism 939 can also be included in head portion960 and 1360, for example, for the positioning of a biased member 939.

Referring now to FIG. 20C, in a further alternate embodiment of adiameter reduction structure 1440, a single unified stand off assembly1445 is formed into a continuous and integrated flanged stand off orflange structure 1445. Flange structure 1445 may take any configurationof head 1460, arm 1456, and base 1451, for example, suitable forperforming the function of limiting the movement of smaller diametersurgical instruments when moved generally parallel off-axis orangularly. Diameter reduction structure 1440 may be at least partiallysegmented with a plurality of slots 1431 defining segmented headportions 1460 and arms 1456. A retention mechanism 1439 can also beemployed to further bias diameter reduction structure 1440. Thisembodiment could also take the structural form of a cantileveredgenerally linear flexible flange structure or an angled stand offstructure at least partially cantilevered and supported by acorrespondingly positioned structure housing.

Diameter reduction structure 1440, with independent stand offs 1450 orconfigured as an integrated unified flange structure stand off 1450, issuitably configured to resist forces in a plane transverse to centrallongitudinal axis “X” and in particular forces in a plane approximatelyorthogonal to the central longitudinal axis “X”. Flange structure 1450is configured to flex or pivot with forces generally aligned with thelongitudinal axis “X” so as to accommodate large diameter surgicalinstruments without any operational adjustments.

In another alternate embodiment the diameter reduction structure is aunified structure wherein the arms are joined to form an annular typestructure configuration and are positioned within the trocar housing asan assembly. The stand off assembly in this embodiment can also includeseparate or integral biased members.

In still another embodiment, one or more diameter reduction structurescould be employed together in series or in one assembly to createparallel diameter reduction structures or diameter reduction structuresof different diameters.

Referring now to FIGS. 21 and 22A, a further alternate embodiment of avalve assembly and diameter reduction structure 1500 includes a diameterreduction assembly 1600 and valve assembly 1700. Valve assembly anddiameter reduction structure 1500 defines a passageway 1505 concentricwith a central longitudinal axis-X.

Diameter reduction assembly 1600 includes a first seal 1525, diameterreduction structure housing or distal housing 1610, a diameter reductionstructure 1640, and a diameter reduction structure foundation element1680. Diameter reduction structure foundation 1680 connects with valveassembly 1700. Seal housing or proximal housing 1710 of valve assembly1700 is configured to be removably connected to cannula 50.

Diameter reduction structure housing 1610 is generally tubular in shapeand includes a tubular wall 1615 defining a distal end portion 1612 anda proximal end portion 1614. Proximal end portion 1614 has a proximallyextending rim 1616 defining a recessed portion or flange 1618. Flange1618 is approximately perpendicular to the longitudinal axis-X andincludes a rim 1619 defining a hole or passageway 1505 aligned withlongitudinal axis-X. Diameter reduction structure housing 1610 in thisconfiguration includes a first seal 1515 positioned distal to flange1618 that is held in position by a first seal support element 1620.First seal support element 1620 also defines a rim 1622 aligned with rim1619. A distal end of rim 1622 forms an edge 1623 with a distal end 1622of seal support element 1620. Distal end portion 1612 includes a flangedportion 1613.

The inside diameter of tubular wall 1615 abuts and is configured toslidingly move in relation to a first member 1630 and a second annularmember 1635. A distal edge 1631 of annular member 1630 is positionedabutting a proximal edge 1636 of second annular member 1635. Secondannular member 1635 has a radially extending protuberance or tab 1637.

Diameter reduction housing 1610 is connected to an annular member 1611extending distally from distal end 1612. A stop 1608 is positioned on adistal end 1609 of member 1611 that abuts a seal support element 1750and defines a first position of housing 1610. Stop 1608 also interfaceswith and is limited by tab 1637 to at least partially limit the proximaltravel of housing 1610 and defines a second position of housing 1610.

Diameter reduction structure 1640 is positioned on a diameter reductionfoundation element 1680. Diameter reduction foundation element 1680 hasa distal end 1682 and a proximal end 1684. Distal end 1682 abuts withseal support element 1750. Element 1680 also abuts with a portion of theinside of annular members 1630 and 1635. Diameter reduction structure1640 is configured to support up to approximately 180° of travel of eachstand off member 1650 from a position extending distally approximatelyparallel to the longitudinal axis to a position extending proximatelyapproximately parallel to the longitudinal axis.

In a first stand off assembly 240 position, stand off members 250 aregenerally positioned in a plane orthogonal the central longitudinal axisand to reduce the operable area of passageway 1505 in. combination withthe structural support of housing 1610. In a second stand off assembly240 position, stand off members 250 are generally positioned at leastpartially distal to the first position. In a third stand. off assembly240 position, stand off members 250 are generally positioned at leastpartially proximal to the first position.

Stand off members 1650 have a head 1660 connected by an arm 1656 to abase portion 1651 with opposing cylindrical end portions 1654. Stand offmembers 250 are connected by a linking mechanism including three linkingmembers 1671 as described in earlier embodiments.

Head 1660 includes a first side 1662 having a generally planar face andan opposing tapered second side 1668 in apposition with first seal 1525when diameter reduction structure 1640 is in the first position. Firstside 1662 includes a cantilevered extension 1661. A third side 1664includes a generally convex portion and beveled side portions 1665. Afourth side 1666, opposing, the third side, has a generally planar facethat is connected with arm 1656 such that the planar face extends tosecond side 1662 and to cantilevered portion 1661. Arm 1656 is a neckdown portion connecting base 1651 and head 1660. Head 1660 also includesa centrally positioned segmented concave notch 1663 approximatelyperpendicular to longitudinal axis-Y. The generally concave shape ofnotch 1663 is configured and dimensioned to accommodate a limited degreeoff axis movement by small surgical tools when diameter reductionstructure 1640 is in a first or initial position.

While diameter reduction structure 1640 is illustrated with stand offassembly 1645 having three stand offs, 1650. and linking mechanism 1670having three linking members 1671, the general configuration of diameterreduction structure foundation 1680 and linking members 1671 arestructurally and operationally similar to earlier embodiments such asthose. of FIGS. 6-8.

Valve assembly 1700 includes a first seal support member 1,750, a secondseal 1765, and a seal housing 1710 configured for connecting to cannula50. In addition, an elastic tubular seal or third seal 1601 is sealinglypositioned over a sliding joint 1699 between valve assembly 1700 anddiameter reduction assembly 1600.

Second seal support element 1750 is positioned between diameterreduction foundation element 1680 and seal housing 1710. Second sealsupport element 1750 has a generally annular in shape with a tubularwall 1755 having an outside cylindrical surface 1756. In addition, adistal end 1752 of second seal support element 1750 seals second seal1765 in position in combination with a proximal end 1714 of seal housing1710.

Seal housing 1710 proximal end portion 1714 includes positions for theseating of the second seal support element 1750 and second seal 1765. Adistal end portion 1712 of seal housing 1710 is configured to mate withcannula 50 utilizing a suitable attachment mechanism such as a bayonetor threaded connection.

Third or tubular seal 1601 has a proximal end 1605 and a distal end1603. Proximal end 1715 is sealingly engaged with flange 1613 ofdiameter reduction housing 1610. Proximal end 1714 of seal housing 1710and distal end 1752 of second seal support element 1750 are positionedto sealingly engage a distal end portion 1603 of third seal 1601. Thirdseal 1601 is configured and dimensioned as a flexible elastic tubularseal positioned over and providing a seal for sliding joint 1699. Thirdseal 1601 is suitably flexible for accommodating the movement ofdiameter reduction housing 1610 between the first position wherein stop1608 is abutting second seal support element 1750 and the secondposition wherein stop 1608 is repositioned proximally and is abuttingtab 1637. In addition, third seal 1601 provides a bias to the firstposition of diameter reduction housing 1610 of seal housing 1610.

Third seal 1601 is preferably fabricated from a flexible and/orstretchable material preferably an extrudable or injected moldablematerial, most preferably an elastomer or elastomeric or elastomermaterial. Third seal 1601 may include a central shape indentation 1601 ato permit longitudinal extension and retraction of structure housing1610. Alternatively, third seal may be completely tubular devoid ofv-shape indentation as depicted in FIG. 23, and have suitableelastomeric properties to permit the seal to stretch during extensionand retraction of the housing 1610. An elastomer material having asuitable thickness for external instrument applications that canencounter rugged handling and is resistant to tearing or penetration,for example, while providing a flexible bias. It is also envisioned thatthird seal 1601 can be readily attached and detached, as required, forautoclaving or sterilization.

Referring now to FIGS. 22A-22C, diameter reduction structure 1640 isbiased to a first position, similar to that of FIGS. 15, 16A, and 20Awherein at least a portion of fourth side 1666 of head 1660 and arm 1656are in apposition with a portion of diameter reduction structure housing1610 and stop 1608 is abutting second seal support element 1750. In thisembodiment, rim 1621 and distal end 1622 of first seal support element1620 are in apposition with at least a portion of fourth side 1666 andarm 1656, respectively and in particular, corner 1623 is positioned atthe junction of arms 1656 and side fourth side 1666. Thus, first sealsupport element 1620 supports stand offs 1650 in the first position byproviding structural support for stand offs 1650 to limit from the offaxis and angular movements of small diameter surgical instruments.

When diameter reduction structure 1640 is deflected distally by a largesurgical instrument, such as shown in. FIG. 13, to the second positionwherein face 1662 is pivoted in the direction of the inside of tubularwall 1755 of second seal support element 1750, stand off members 1650are accommodating the increased diameter of the large surgicalinstrument without any external adjustments by the surgeon or operator.Stand off members 1640, however; retain their bias to the firstposition.

When the large surgical instrument is withdrawn proximally through valveassembly and diameter reduction structure 1500, the combination of thebias and elastic nature of stand off members 1650 may bind with thelarge instrument. To preclude undesirable binding, distal end 1612 isslidingly engaged with first annular member 1630, second annular member1635, and second seal support element 1750 such that the diameterreduction housing 1610 slides proximally until the instrument ceases tobind or stop 1608 abuts tab 1637. The proximal movement of diameterreduction structure 1610 from the first housing 1610 position defines anincreased volume within diameter housing 1610 that is suitable for standoff members 1650 to pivot proximally to the third position and at leastpartially increase the operable area of passageway 1505 from the secondoperable area to a third operable at least wherein the operable area isincreased similar to that of the second position of the stand offassembly such that the large instrument can be withdrawn with limitedresistance.

Additional alternative embodiments for precluding binding include acatch or an engaging receptacle for each stand off in the secondposition with an external release mechanism, for example, or a frictionreducing means such as one or more wheels positioned on second side 1668and/or third side 1664 that could accommodate the withdrawal of thelarge instrument while in a distal or second position by the rotation ofthe wheel and still provide adequate resistance to movements of smallsurgical instruments when in the first position.

Referring now to FIG. 24, there is illustrated another embodiment of thepresent disclosure. System 2000 includes seal assembly 2002 and cannulaassembly 2004 to which the seal assembly 2002 is mounted. Seal assembly2002 defines a seal housing consisting of a plurality of componentsforming an outer member of the seal assembly 2002, and diameterreduction structure for limiting excessive off-axis and angularmovements of small diameter surgical instruments as discussedhereinabove. Seal assembly 2002 defines seal axis “x”. Seal assembly2002 includes first or proximal seal subassembly 2006 and second ordistal seal subassembly 2008 which is connected to cannula assembly2004. First seal subassembly 2006 is adapted for releasable connectionto second seal subassembly 2008 and incorporates the diameter reductionstructure.

With reference now to FIG. 25-27, in conjunction with FIG. 24, first andsecond seal subassemblies 2006, 2008 of seal assembly 2002 will bediscussed. First seal subassembly 2006 includes end cap 2010, septumseal 2012 and diameter reduction housing 2014. Diameter reductionhousing 2014 includes first and second reduction housing components2016, 2018 which house stand-off elements 2020. In general, stand-offelements 2020 are interconnected and pivot to permit passage of aninstrument. Stand-off elements 2020 are biased to an initial position byelastomeric O-ring 2022. O-ring 2022 is received within recess 2020 r ofeach stand-off element 2020 as shown in FIG. 26. When stand-off elements2020 pivot downwardly (shown in phantom in FIG. 26) upon insertion of aninstrument, O-ring 2022 stretches to permit this movement of thestand-off elements 2020. Upon removal of the instrument, the stand-offelements 2020 return to their initial position in transverse relation tothe axis “x” under the influence of the O-ring 2022. The remainingcomponents of first seal subassembly 2006 are substantially similar totheir corresponding components disclosed and discussed in the priorembodiments, and reference is made hereinabove for a further discussionof the structure and functionality of these components.

In one further aspect of the present embodiment, diameter reductionhousing 2014 includes mounting tabs 2024 radially spaced about interiorwall 2026 of second reduction housing component 2018. As seen in FIG. 25and FIG. 27, mounting tabs 2024 serve to releasably secure first sealsubassembly 2006 to second seal subassembly 2008 as will be discussed.

Second seal subassembly 2008 includes stationary ring member 2028,duckbill valve housing 2030, zero closure or duck bill valve 2032supported within the valve housing 2030, and manual lock member 2034.Stationary ring member 2028 defines first annular wall 2036 on itsproximal side. Annular wall 2036 incorporates small and large recesses2038, 2040 arranged in diametrical opposed relation as shown. Firstannual wall 2036 of stationary ring member 2028 is received withinannular gap 2042 defined between walls 2044, 2046 of first and secondreduction housing components 2016, 2018, respectively (FIG. 26). Smalland large recesses 2038, 2040 receive corresponding pairs of positioninglegs 2048, 2050 of reduction housing 2014. As best depicted in FIGS. 28and 29, the respective distances between the positioning legs 2048, 2050and corresponding lengths of recesses 2038, 2040 (identified asdistances and lengths “a” and “b”) ensure proper orientation ofreduction housing 2014 within, or relative to, stationary ring member2028 during assembly.

Stationary ring member 2028 further includes second annular wall 2052disposed on the distal side of the stationary ring member 2028. Secondannular wall 2052 includes partial annular slot 2054 therein and aplurality of radially spaced grooves 2056 in its outer surface. A singlelocking tab 2058 is disposed within each groove 2056. The functioning ofpartial slot 2054, spaced grooves 2056 and locking tabs 2058 will bediscussed in greater detail hereinbelow.

As best depicted in FIGS. 25 and 29, duck bill valve housing 2030includes annular wall 2060 which defines central aperture 2062. Annularwall 2060 defines three grooves 2064 proximal aperture 2062. Grooves2064 accommodate mounting tabs 2024 of diameter reduction housing 2014during assembly of first and second seal subassemblies 2006, 2008. Duckbill housing 2030 includes a plurality of axial depending legs 2066.Legs 2066 of duck bill valve housing 2030 may include rectangularopenings 2068.

In one preferred arrangement, manual lock member 2034 is secured to duckbill housing 2030 in fixed relation therewith. Manual lock member 2034includes a plurality of recesses 2070 defined in its outer surface.Recesses 2070 receive corresponding depending legs 2066 of duck billhousing 2030. Recesses 2070 each include mounting tabs 2072 (as seen inFIG. 25) which are received within rectangular openings 2068 ofdepending legs 2066 of duck bill housing 2030 in snap relation therewithto secure the two components (see also FIG. 26). Manual lock member 2034and duck bill housing 2030 capture the peripheral rim 2074 of duck billvalve 2032 to secure the duck bill valve 2032 between the twocomponents.

Manual lock member 2034 and duck bill housing 2030 are at leastpartially disposed within stationary ring member 2028 and are adaptedfor rotational movement relative to the stationary ring member 2028.Manual lock member 2034 includes grip 2076 which extends radiallyoutwardly for engagement by the user. Grip 2076 includes transverse leg2078 which is accommodated within partial annular slot 2054 ofstationary ring member 2028 and traverses the slot 2054 during rotationof manual lock member 2034 and duck bill housing 2030. Manual lockmember 2034 is adapted for rotational movement between a first positioncorresponding to a release position which permits mounting and/orrelease of first subassembly 2006 from second subassembly 2008, and asecond position corresponding to a lock position which secures firstsubassembly 2006 to the second subassembly 2008. An O-ring seal 2080 maybe positioned about the circumference of duck bill housing 2030 to forma substantial seal between the duck bill housing 2030 and diameterreduction housing 2014.

In other embodiments, the manual lock member 2034 is slidably receivedby duck bill housing 2030. The manual lock member 2034 is then slidablewith respect to stationary ring member 2028.

With reference to FIGS. 24-26, cannula assembly 2004 includes cannulahousing 2082 and cannula sleeve 2084 extending from the housing 2082.Cannula housing 2082 includes vertical legs 2086 which are positionedwithin grooves 2056 of stationary ring member 2028. Legs 2086 preferablyinclude internal ledges 2088 advantageously dimensioned to accommodatelocking tabs 2058 disposed within the grooves 2056 of stationary ringmember 2028 to fixedly secure the two components. Cannula sleeve 2084defines longitudinal passage 2090 which permits passage ofinstrumentation. Cannula sleeve 2084 may be secured to cannula housing2082 by corresponding tongues 2092 and grooves 2094 of the cannulasleeve 2084 and the cannula housing 2082 respectively. An O-ring seal2096 may be positioned within cannula housing 2082 for forming a sealwithin the housing 2082 adjacent these components.

In use, second seal subassembly 2008 of seal assembly 2002 is mounted tocannula housing 2082. In this regard, vertical legs 2086 of cannulahousing 2082 are aligned with grooves 2056 of stationary ring member2028 and the ring member 2028 is advanced whereby the locking tabs 2058of the ring member 2028 securely engage the internal ledges 2088 withinthe vertical legs 2086. Thereafter, when it is determined that thediameter reduction structure is needed, for example, in use with a smalldiameter instrument, first seal subassembly 2006 is positioned relativeto second seal subassembly 2008 as depicted in FIGS. 27-29. In thisposition, positioning legs 2048, 2050 of first seal subassembly 2006 arealigned with the corresponding recesses 2038, 2040 of second sealsubassembly 2008 (FIGS. 25 and 27). In addition, manual lock member 2034is placed in the first or release position of FIG. 29. In this position,mounting tabs 2024 of the first seal subassembly 2006 are in generalalignment with mounting recesses 2064 of the annular plate 2060 of duckbill housing 2030 of the second seal subassembly 2008. First sealsubassembly 2006 is then mounted to second seal subassembly 2008 wherebypositioning legs 2048, 2050 are positioned in respective recesses 2038,2040 and mounting tabs 2024 are received within mounting grooves 2064 ofduck bill housing 2030. Manual lock member 2034 is then rotated aboutaxis “a” from the first or release position depicted in FIG. 30 to thesecond or lock position depicted in FIG. 31. This movement of manuallock member 2034 causes corresponding rotational movement of duck billhousing 2030 to displace the mounting grooves 2064 whereby mounting tabs2024 are captured beneath annular wall 2060 of duck bill housing 2030.In this position, first seal subassembly 2006 is secured to second sealsubassembly 2008. The procedure is continued by introducing aninstrument through the seal assembly 2002 and cannula assembly 2004, andperforming the desired surgical procedure.

It is noted that duck bill housing 2030 and manual lock member 2034 maybe a single component monolithically formed during manufacture. Inaddition, it is envisioned that the second seal subassembly 2008 may bea component of the cannula housing or sleeve housing 2082, and suppliedwith the cannula assembly 2004. In the alternative, second sealsubassembly 2008 may replace the cannula housing 2082 in its entiretyand serve as the sleeve housing. It is further envisioned that othermodified first seal subassemblies, for example, with or without diameterreduction structure, may be adapted for use with the second sealsubassembly 2008.

Although the illustrative embodiments of the present disclosure havebeen described herein with reference to the accompanying drawings, it isto be understood that the disclosure is not limited to those preciseembodiments and that various other changes and modifications may beaffected therein by one skilled in the art without departing from thescope or spirit from the disclosure. All such changes and modificationsare intended to be included within the scope of the appended claims.

1.-19. (canceled)
 20. A surgical system, which comprises: a cannulaassembly including a cannula housing and a cannula sleeve extending fromthe cannula housing, the cannula sleeve defining a longitudinal axis andhaving a longitudinal passageway to permit passage of a surgicalinstrument; a second seal subassembly including a second housing adaptedfor mounting to the cannula housing, a lock member disposed within thesecond housing and adapted for rotational movement relative to thelongitudinal axis between a first position and a second position, thelock member having an annular member defining a central aperture forpassage of the surgical instrument and a plurality of internal mountingrecesses communicating with the central aperture, and a manual gripmember connected to the lock member and depending radially outwardlyrelative to the longitudinal axis to extend external of and be movablerelative to the second housing, the manual grip member being directlymovable by the surgeon to move the lock member between the first andsecond positions; and a first seal subassembly for releasably mountingto the second seal subassembly, the first seal subassembly including afirst housing having a seal member adapted to permit passage of asurgical object in substantial sealed relation therewith and a pluralityof internal mounting tabs configured to be received or released by themounting recesses of the lock member when the lock member is in thefirst position and to be secured to the lock member when the lock memberis in the second position.
 21. The surgical system according to claim20, wherein the mounting recesses of the lock member of the second sealsubassembly are in general alignment with the internal mounting tabs ofthe first housing of the first seal subassembly when the lock member isin the first position.
 22. The surgical system according to claim 20,wherein the mounting recesses of the lock member of the second sealsubassembly are displaced from the internal mounting tabs of the firsthousing of the first seal subassembly when the lock member is in thesecond position.
 23. The surgical system according to claim 22, whereinthe lock member is adapted for rotational movement to displace themounting recesses of the lock member thereby capturing the mounting tabsbeneath the annular wall of the lock member.
 24. The surgical systemaccording to claim 20, wherein the second housing of the second sealsubassembly further comprises a stationary ring including small andlarge recesses and the first seal subassembly further comprises a pairof positioning legs corresponding to the small and large recesses of thestationary ring, the small and large recesses of the second sealsubassembly configured to receive the positioning legs of the first sealsubassembly to ensure proper orientation of the first and second sealsubassemblies during mounting.
 25. The surgical system according toclaim 20, wherein the manual grip member is dimensioned to extendthrough a partial annular slot in the second housing of the second sealsubassembly.
 26. The surgical system according to claim 25, wherein themanual grip member includes a leg extending through the partial annularslot of the second housing for traversing the partial annular slotduring rotation of the manual grip member between the first and secondpositions.
 27. The surgical system according to claim 20, wherein thesecond seal subassembly includes a zero closure valve adapted to open topermit passage of the surgical instrument and to substantially close inthe absence of the surgical instrument.
 28. The surgical systemaccording to claim 20, wherein the lock member is adapted to rotatethrough an arc of rotation of at least about thirty (30) degrees withrespect to the longitudinal axis during movement between the first andsecond positions thereof.
 29. The surgical system according to claim 20,wherein the first seal subassembly includes at least two stand-offelements mounted within the first housing distal of the seal member, thestand-off elements adapted for pivotal movement between an initialposition and a pivoted position to permit passage of the surgicalinstrument, the stand-off elements being normally biased to the initialposition to urge the surgical instrument into general alignment withrespect to a longitudinal axis of the first housing.
 30. The surgicalseal assembly according to claim 29 wherein the at least two stand-offelements are operatively coupled such that movement of a first stand-offelement between the initial and pivoted positions causes correspondingmovement of a second stand-off element.